Description

Chromotropic Acid Disodium Salt Dihydrate is a high-purity analytical reagent and key chemical intermediate. This compound is critically important for its role as a sensitive and selective chromogenic agent in analytical chemistry. It is primarily needed by manufacturers and laboratories in the chemical, pharmaceutical, and environmental testing industries for precise quantitative analysis.

Application

• Analytical Chemistry Reagent: Widely used as a sensitive colorimetric reagent for the spectrophotometric determination of formaldehyde, nitrite, and various aldehydes.
• Pharmaceutical Analysis: Employed in the assay and impurity profiling of drug substances and formulations where formaldehyde or related compounds are present or generated.
• Environmental Testing: Applied in water and air quality monitoring kits and procedures for detecting trace levels of formaldehyde and other pollutants.
• Dye & Pigment Intermediate: Serves as a key precursor in the synthesis of specific azo dyes and colorants.
• Biochemical Research: Utilized in laboratory protocols for staining and detection methods in histology and biochemistry.
• Industrial Process Control: Used for in-process testing and quality control in industries like resins, textiles, and disinfectants where formaldehyde is involved.

Basic Information

Product Name	Chromotropic Acid Disodium Salt Dihydrate
CAS No.	5808-22-0
Molecular Formula	C10H6Na2O8S2 · 2H2O
Molecular Weight	400.24 g/mol
Synonyms	1,8-Dihydroxynaphthalene-3,6-disulfonic Acid Disodium Salt Dihydrate; 4,5-Dihydroxynaphthalene-2,7-disulfonic Acid Disodium Salt; Chromotropic Acid Sodium Salt; Disodium Chromotropate; Disodium 4,5-Dihydroxy-2,7-naphthalenedisulfonate; Na2CTA
EINECS	227-357-5

Quality Control

Our Chromotropic Acid Disodium Salt Dihydrate is manufactured under a strict quality management system. Each batch undergoes rigorous analytical testing to ensure it meets high-purity standards suitable for analytical and research applications. A comprehensive Certificate of Analysis (COA) detailing purity, identity, and impurity profiles is provided with every shipment to guarantee traceability and compliance.

Storage

Preserve in a tightly closed container, protected from light. Store in a cool, dry, and well-ventilated place at room temperature (15-25°C). Due to its hygroscopic nature, the container must be kept tightly sealed to prevent moisture absorption, which can affect product performance and stability.

Specification

Item	Specification
Appearance	White to off-white crystalline powder
Identification (IR)	Conforms to standard
Assay (HPLC)	≥ 98.0%
Water Content (KF)	7.0 - 10.0%
pH (5% Solution)	6.0 - 8.0
Solubility	Clear, colorless solution in water
Heavy Metals (as Pb)	≤ 20 ppm

Note: Specifications can be tailored. Please contact us for the detailed technical data sheet of a specific grade.